SUMMARY
Metrologists at the Fluke Calibration Laboratory service a range of customer equipment. Earlier this year, they upgraded their workflows and hardware to improve throughput.
The most impactful change the team made was swapping their Fluke 8508A 8.5-Digit Reference Multimeter for an 8588A Reference Multimeter. With the 8588A, the team:
- Cut calibration time in half
- Eliminated a massive backlog of work
- Experienced decreased downtime and fewer work stoppages
- Saw 95% on-time lab performance after implementation
BACKGROUND
The Fluke Calibration Laboratory in Everett, Washington services a wide variety of customer equipment, from multimeters to calibrators. In 2024, the lab underwent an internal initiative focused on increasing throughput.
For a week, specialists took stock of lab workflows and devised new methods to improve their processes. They also evaluated the status of lab equipment to determine which machines they could upgrade to help streamline and speed up the calibration process.
CHALLENGES
One of the biggest issues facing the Fluke Calibration Laboratory was keeping up with customer demand.
“In the service center, we were practically tripping over customer 55XXs,” says Ronald Chaussee, a metrologist at Fluke Calibration. “We had so much backlog, we didn’t know where to put it.”
The lab has two main calibration setups that allow specialists to handle a wide range of customer equipment: a legacy station and an advanced station.
The legacy station runs a Keysight 3458A 8.5-Digit Multimeter, which works quickly but doesn’t provide the accuracy needed for all calibration jobs. The advanced station, which employs a Fluke 5790B AC Measurement Standard and an 8508A 8.5-Digit Reference Multimeter, offers a higher degree of accuracy suited for more precise calibrations. But with it, metrologists had to sacrifice speed.
“We knew one of our major contributors to the amount of time it took to do the calibration was how quickly the 8508A triggered,” says Jonathan Spradlin, a metrologist at Fluke Calibration. “We were very aware that compared to our legacy station, the 8508A was much slower in its time to acquire measurement.”
Because of the measurement delay, the work just kept piling up. During their internal initiative to increase throughput, the team reevaluated their equipment needs and decided they needed an upgrade. They turned to the Fluke 8588A Reference Multimeter because it had a lot of the same features as the 3458A but with better speed and accuracy specs.
IMPLEMENTATION
With their decision made, the team made it official and installed the 8588A in the lab as a replacement for the 8508A.
During the initiative, the thought process was, “Let’s just see if we could throw it in emulation mode and see what it does,” says Spradlin. The team wanted to see if it could take simple measurements quickly, though acknowledged that emulation mode does have limitations. For example, while emulation could simulate the command set, it could not simulate the state of the 8508A completely. That’s why the team recommends verifying all measurements taken in emulation mode the first time.
When used in the right setting, this feature gave the team a huge advantage. “We were kind of blown away by how much of a difference it made,” Spradlin says.
Emulation mode enabled the 8588A to perform many of the same functions as the 8508A without any modifications. In many cases, the team could seamlessly take measurements without needing to change the software’s source code. For others, they had to adjust the code in MET/CAL in order to accurately conduct certain tests.
“Converting the software over was not trivial, but it was easy,” Chaussee says. Even without significant MET/CAL coding experience, he found it relatively simple to adjust the settings for emulation, which is a feature that customers have access to as well. Switching to the 8588A was a much easier process than it would have been if the team swapped the 8508A with a different measurement standard that did not have emulation mode.
Digitizing measurements was also remarkably easier with the 8588A. Traditional methods require logging readings in memory and then exporting data so that it can be processed. But the 8588A can do a “lite” version of digitization, allowing metrologists to measure AC voltage and current and digitize readings right on the multimeter’s front panel.
“We didn't have to play with settings and then pull a file out, put it in Excel, and chart it and graph it. We could just sit there and do some measurements on the front panel, see the waveform, know that our settings were correct, and then we knew what settings to put into our MET/CAL procedure to be able to get the answer that we wanted significantly faster,” says Michael Brown, a metrologist at the Fluke Calibration Laboratory.
For digitization, the meter utilizes an advanced triggering system that has three trigger events capable of getting a sample of readings. For example, the 8588A might gather a group of samples at the top of a square wave, a group at the bottom of the square wave, and the min, max, and span values. Then, the meter instantaneously generates the peak-to-peak voltage of a square wave.
This process is suitable and accurate for basic digitization of measurements. If the team wanted to go deeper and digitize elements like harmonic distortion, it would require traditional digitization methods. “Fortunately, the 8588A has both,” Brown says.
RESULTS
With the 8508A, it took the team eight hours to calibrate a single 55XX series calibrator. But when they swapped in the 8588A, it only took four hours — a drastic 50% reduction in calibration time.
The new equipment enabled them to tackle the growing pile of customer tools that needed to be calibrated. In just a few months, the team tore through the backlog. Now, they’re running 95% on time, and have even had a few times where they’ve missed throughput goals due to a lack of work.
“The shelves are not empty, but they’re not what they were for sure,” Spradlin says.
The lab is also experiencing less downtime. There are fewer instances of having to “interrupt or halt production because some portion of the station is not operating,” Brown says. Chaussee agrees that the 8588A has made their equipment setup a lot more reliable than it was before. “I am fighting significantly less fires for the advanced stations than we ever did for the legacy,” he elaborates.
The team is already thinking about ways that they can use the 8588A to improve other parts of the lab. “We saw significant improvements that radically change how we think about other operations,” Brown says.